/*
 * ProGuard -- shrinking, optimization, obfuscation, and preverification of Java bytecode.
 *
 * Copyright (c) 2002-2018 GuardSquare NV
 *
 * This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public
 * License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later
 * version.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
 * warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along with this program; if not, write to the Free
 * Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
 */
package proguard.optimize.info;

import proguard.classfile.*;
import proguard.classfile.visitor.ClassVisitor;

/**
 * This ClassVisitor delegates its visits to one of two other given ClassVisitor instances, depending on whether the
 * classes are marked as simple enums or not.
 *
 * @see SimpleEnumMarker
 *
 * @author Eric Lafortune
 */
public class SimpleEnumFilter implements ClassVisitor {
    private final ClassVisitor simpleEnumClassVisitor;
    private final ClassVisitor otherClassVisitor;

    /**
     * Creates a new SimpleEnumClassFilter.
     *
     * @param simpleEnumClassVisitor the class visitor to which visits to classes that are marked to be simpleEnum will
     *        be delegated.
     */
    public SimpleEnumFilter(ClassVisitor simpleEnumClassVisitor) {
        this(simpleEnumClassVisitor, null);
    }

    /**
     * Creates a new SimpleEnumClassFilter.
     *
     * @param simpleEnumClassVisitor the class visitor to which visits to classes that are marked as simple enums will
     *        be delegated.
     * @param otherClassVisitor the class visitor to which visits to classes that are not marked as simple enums will be
     *        delegated.
     */
    public SimpleEnumFilter(ClassVisitor simpleEnumClassVisitor, ClassVisitor otherClassVisitor) {
        this.simpleEnumClassVisitor = simpleEnumClassVisitor;
        this.otherClassVisitor = otherClassVisitor;
    }

    // Implementations for ClassVisitor.

    public void visitProgramClass(ProgramClass programClass) {
        // Is the class marked as a simple enum?
        ClassVisitor classVisitor =
            SimpleEnumMarker.isSimpleEnum(programClass) ? simpleEnumClassVisitor : otherClassVisitor;

        if (classVisitor != null) {
            classVisitor.visitProgramClass(programClass);
        }
    }

    public void visitLibraryClass(LibraryClass libraryClass) {
        // A library class can't be marked as a simple enum.
        if (otherClassVisitor != null) {
            otherClassVisitor.visitLibraryClass(libraryClass);
        }
    }
}